Because of their relatively low recording (reading and writing) density, conventional magnetic heads are very limited in their applications for recording (writing) and retrieving (reading) mega- or giga-scale massive amounts of data that have become a trend in the informations industry. Furthermore, conventional magnetic heads also suffer from the weakness of requiting a laborious manufacturing procedure for making the same.
In order to record mass information, multiple-track read and write magnetic heads have been proposed in the art. For example, U.S. Pat. Nos. 5,224,002 and 5,251,088, the contents of which are explicitly incorporated herein by reference, disclose magnetic write and read heads prepared using a thin-film technology. Magnetic thin-film materials (such as Fe, Co, Ni, or their alloys) are used as a core material and a conducting material, such as Cu, is used as a thin-film coil to fabricate write heads. The read head comprises a plurality of solid-state elements, such as magneto-resistance elements, which are formed into a plurality of magnetically sensitive layers in plans parallel to the plan of a substrate and the passage of the track to read a large number of tracks. The magnetically sensitive thin-flints are inserted into a magnetic circuit, which has the shape of a ring with an open gap. These multiple-track heads have been applied by Phillips Electronics Corp. in the production of digital compact: cassette (DCC) devices, and the resultant product can simultaneously read or write up to 18 tracks of data. Although this is a substantial improvement over the conventional magnetic heads, the recording density is still less than what would be desired, especially in light of the rapid advancement of the laser based optical recording devices.